Amphenol Advanced Sensors Thermometrics Infrared Thermopile Sensors Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Non-contact Temperature Measurement Infrared Thermopile Sensors What is Infrared? • • Form of electromagnetic wave Extends from 0.7 m -1000 m ‒ Near infrared: 0.7 m - 2.5 m ‒ Intermediate infrared: 2.50 m - 25.0 m ‒ Far infrared: over 25.0 m • Most IR sensors based on two regions … 3 - 5m and 8 - 12 m 3/ Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Infrared Radiation • Electromagnetic emission and absorption • Occurs at the speed of light • Travels in a straight line • Takes place across a vacuum • Passes through many crystalline, plastic, gaseous materials • Does not penetrate metals 4/ Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Radiated Infrared Energy The warmer the source, the more energy it emits W = δεT4 W = Radiant flux emitted per unit area (W/cm2) Infrared Sensing Hot objects emit infrared (IR) and visible radiation as a function of surface temperature δ = Stefan-Boltzmann constant ε = Emissivity T = Absolute temperature of target (K) As the temperature of the source increases, the wavelength at which most of the energy is radiated decreases λmax = b/T b = Wien’s displacement constant As an object gets hotter, not only does it radiate more, but the peak wavelengths it emits get shorter Objects have different wavelengths of radiation 5/ Copyright © 2015 Amphenol. All rights reserved. Radiation. Reflection. Transmission. object ε R ε+R+T=1 ε = emissivity FOV T R = Reflectance T = Transmittance 6/ Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Approximate Emissivity Figures Material Radiation Material Radiation Paper 0.92~0.94 Aluminum (luster) 0.095 Plastic 0.95 Aluminum oxide 0.26~0.42 Ceramic 0.90 Copper (luster) 0.05 Water 0.95~0.963 Copper oxide 0.78 Human skin 0.985 Cast Iron (luster) 0.21 Paint (lusterless) 0.95 Nickel (luster) 0.045 Paint (luster) 0.9 Nickel oxide 0.37 Epoxy/Glass 0.86 Stainless steel 0.16~0.44 7/ Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Thermopile Construction Seebeck effect A Th Tc=Tamb B + Δ V = α ΔT = (αA- αB)(Th-Tc) - To increase the sensitivity (high Seebeck coefficient): • Higher Th, lower T • More thermocouples • Heavier inert gas filling • Thin diaphragm with lower thermal conductance • Highly transmitted IR filter • High efficient IR absorber Sensing Mechanism Thermopile Detector Packaging 8/ Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors What is a Thermopile? • Serially-interconnected array of thermocouples • Each thermocouple formed by the junction of two dissimilar materials • Thermocouple array placed across hot and cold regions of structure • Hot junctions thermally isolated from the cold junctions • Cold junctions placed on silicon substrate for effective heat sinking • Hot junctions formed over thin diaphragm that thermally isolates hot and cold junctions • In hot regions, a black body absorbs the infrared energy, raising temperature according to the intensity of incident energy 9/ Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Unique Features Thermopile sensors have unique properties not offered by other detectors: • Response to broad infrared spectrum • No source of bias voltage or current needed • Inherently stable response to DC radiation 10 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Features of Thermometrics Thermopile IR Sensors PRODUCT COMPARISON TABLE OF ZTP SERIES Part Number Package type ZTP-101T Thermopile Thermistor Resistance Sensitivity(Vircal) Filter transmittance resistance(㏀ ) & B-Value @Tobj=40℃ range(um) @Tamb=25℃ @Tamb=25℃ Field of View Lead length Window size (mm) (mm) 1.0mV 200 30㏀_3811 6~13 50 degree 6.7 Di a 2.5 0.6mV 50 10㏀_3970 6~13 55 degree 5 Di a 2.5 85 degree 13.5 Di a 2.4 TO-39(TO-5) ZTP-115 ZTP-135SR TO-46(TO-18) 1.3mV 60 100㏀_3960 6~13 Part Number Sensor type Main Application Output type Communication protocol Pixel Q'ty ZTP-115M Si ngl e modul e Genera l Indus tri a l , Mi crowa ve Oven, Appl i a nces , etc. Ana l og Vol tage Si ngl e Range of Ambient Input supply Measuring Temperature voltage Temperature(℃) Range(℃) -40 ~ 145 -20 ~ 120 +5V Main Application Mass Production Non-contact Tempera ture Mea s urement Thermometry, Medi ca l , Genera l Indus tri a l , Occupa ncy Detection, HVAC, etc. Yes Module Size (mm) Mass production 17 X 33 Yes 11 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Thermopile Characteristics V = S.(TOB - TAB) V = Output voltage from thermopile TO = Object temperature in K TA = Ambient temperature in K S = Sensitivity coefficient B = Coefficient (~4) S and B are determined by measurement 12 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Temperature Compensation • Output from thermopile varies with both ambient and object temperature • Need to know the ambient temperature to calculate the object temperature • Thermometrics standard thermopiles supplied with integrated thermistor for compensation • Options include customer-specified thermistor or external temperature compensation (no internal thermistor) 13 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Various Filter Options Filter Material Transmission Range Application Appliances, Microwave Oven Standard Silicon 6~13um Medical, Ear Thermometer Automotive, Tire Temperature HVAC, Human Body Detection F1 Silicon 8~14um F2 Sapphire 2~5um F3 CaF2 1~10um NDIR Silicon Occupancy Detection, Intruder alarms Flame Detection, Analysis equipment 3.99±1% reference 4.65±1% CO gas detection 4.26±1% CO2 gas detection 3.45±1% HC gas detection 14 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Standard ZTP Series ZTP-101T Cap / Can ZTP-115 ZTP-135SR The ZTP series of IR thermopile sensors are used for non-contact surface temperature measurement. The product consist of thermoelements, flat IR filter, a thermistor for temperature compensation in a hermeticallysealed TO package. There are also a variety of filters available to help maximize performance in specific applications. Lead Length Filter 15 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Modules Standard ZTP Series Reflector ZTP-115M The ZTP-115M is a single IR module. It consists of a thermopile, IR sensor, signal conditioning and voltage output. Window Conditioning electronics 16 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Modules ZTP-115M Signal Conditioning & Amplification 5 Output(V) 4 3 2 1 0 -20 0 20 40 60 80 100 120 140 160 o Object Temperature( C) 17 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Modules ZTP-115M Compensated Output Temperature Deviation ( C ). 30C 60C 90C 5 3 1 -1 -3 -5 0 10 20 30 40 50 60 70 80 90 100 Ambient Temperat ure (C) 18 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Modules ZTP-115M Field of View 1.0 Horizontal Vertical Normalized Output 0.8 V(-) 0.6 MODULE H(+) 0.4 H(-) V(+) 0.2 H(+/-) : Horizontal Direction V(+/-) : Vertical Direction 0.0 -20 -10 0 10 20 Degree (3) Spot Size of Normalized Output(above 10%) Φ50 ZTP-115M 100 mm Φ90 200 mm Φ130 300 mm 19 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Example Interface Circuit NTC Thermistor used for compensation of the ambient factors. Op Amp used to amplify the output voltage signal from the thermopile 20 / Copyright © 2015 Amphenol. All rights reserved. Infrared Thermopile Sensors Typical Applications Ear, Forehead Thermometry Non-contact Temperature Measurement Thermometry Microwave Ovens Induction Heater Cookers Air Conditioners Occupancy Detection Lighting Underfloor Heating Control HVAC / Automotive 21 / Copyright © 2015 Amphenol. All rights reserved.